UTM Zone Calculator
The Universal Transverse Mercator (UTM) system slices the world into 60 north-south zones, each 6 degrees of longitude wide, so that a flat map of each zone has minimal distortion. To project a latitude and longitude into UTM easting and northing you first need the zone. This calculator returns the zone number, hemisphere, central meridian, and latitude band letter for any point, applying the widened zone 32 over southwest Norway and the irregular Svalbard zones. If your point lies beyond 80S to 84N, it tells you that the polar UPS system applies instead.
UTM zone formula
zone = floor((longitude + 180) / 6) + 1
central meridian = zone * 6 - 183 (degrees)
hemisphere = latitude >= 0 ? North : South
band letter = C..X from -80 in 8-degree steps (X is 12 deg)
Norway: 56-64N, 3-12E forces zone 32
Svalbard: 72-84N widens 31, 33, 35, 37
Zones are numbered 1 to 60 eastward from 180W. The central meridian carries the 0.9996 scale factor. The band letter combined with the zone number gives the grid zone designation used in MGRS.
UTM zone context
- 60 zones cover the globe, each 6 degrees wide, numbered 1 to 60 from the antimeridian eastward.
- Latitude band letters run C to X, skipping I and O to avoid confusion with 1 and 0.
- Zone 32 is widened for southwest Norway, a long-standing cartographic convention.
- Svalbard zones 31, 33, 35 and 37 are widened, and 32, 34 and 36 are not used.
- The poles (beyond 80S to 84N) use Universal Polar Stereographic, not UTM.
UTM zone: frequently asked questions
How is the UTM zone number determined?
The Universal Transverse Mercator system divides the globe into 60 zones, each 6 degrees of longitude wide. Zone number = floor((longitude + 180) / 6) + 1. Zone 1 covers 180W to 174W, and zones increase eastward. The central meridian of a zone is at (zone number times 6) minus 183 degrees.
What are the Norway and Svalbard exceptions?
Two regions break the regular 6-degree pattern. Zone 32 is widened to cover southwest Norway (latitudes 56N to 64N, longitudes 3E to 12E). Around Svalbard (72N to 84N) zones 31, 33, 35 and 37 are widened and zones 32, 34 and 36 are skipped. This calculator applies both exceptions.
What is the UTM latitude band letter?
Latitude bands are lettered C to X (omitting I and O) in 8-degree steps from 80S to 84N; band X is 12 degrees. The band letter is part of the MGRS grid reference. Bands A, B, Y and Z denote the polar UPS regions outside the 80S to 84N UTM range.
What is the central meridian and why does it matter?
Each UTM zone has a central meridian where scale distortion is minimised (scale factor 0.9996). Coordinates are measured east and north of this meridian. Knowing the central meridian is the first step in projecting latitude and longitude into easting and northing.
Does UTM cover the poles?
No. UTM covers 80S to 84N. The polar regions use the Universal Polar Stereographic (UPS) system instead. If your latitude is outside that range, this calculator reports that UPS applies.
Official sources
- U.S. National Geospatial-Intelligence Agency: UTM and grid coordinate systems.
- U.S. Geological Survey: map projections and UTM.
Reviewed by the CalculatorHub team, edited by James Graham, 17 June 2026. See our methodology.